1. (a) Field of the Invention
The present invention relates to an improved sprinkler nozzle, more particularly to an adjustable sprinkler nozzle that is adjustable up to 360 degrees.
2. (b) Description of the Prior Art
U.S. Pat. No. 4,579,285 discloses an adjustable sprinkler system (S), which, as shown in FIGS. 16 to 18, comprises an outer tube 6, an inner tube 7, a cap 8 and a screw bolt 9. The upper edge of the inner tube 7 is provided with a spiraling edge 71, and the bottom edge of the cap 8 is correspondingly provided with a spiraling edge 81, thereby forming an adjustable nozzle with a variable outlet orifice. By rotating the cap 8 to displace upwardly and downwardly within the inner tube 7, the flow and speed of the water can be controlled. However, such a sprinkler system (S) has the following drawbacks:
1. Since the water that flows via the bottom portion of the outer tube 6 into a passage 72 is ejected from the outlet orifice between the spiraling edges 81, 71 between the cap 8 and the inner tube 7, the water will flow along the inclined face of the spiraling edges and is sprinkled to the surrounding by a radial force (P1). However, since the spiraling flow of water is not barred in the lateral directions, a larger water jet (W) will be formed at a longitudinal drop face 82 between the higher face and the lower face of the spiraling edge 81, as shown in FIG. 18, thereby resulting in uneven sprinkling of water.
2. Furthermore, to turn off the sprinkler system (S), the cap has to be rotated downwardly so that the spiraling edge 81 abuts against the spiraling edge 71 of the inner tube 7. However, since there is a drop face between the spiraling edges 81, 71, a gap may be present between the abutting spiraling edges 81, 71 during closing, thereby resulting in water leakage.
In U.S. Pat. No. 5,556,036 entitled xe2x80x9cAdjustable Arc Sprinkler Nozzle,xe2x80x9d in order to improve the above-mentioned drawbacks, with reference to FIGS. 19 and 20, a stop member 83 is disposed at the outer periphery of a longitudinal drop face 82 at the joint of a spiraling edge 81 of a cap 8 to provide a lateral force to thereby prevent the formation of a larger water jet (W) at the drop face 82 associated with the prior art shown in FIG. 18. Hence, when the water is sprayed in radial directions (P1), some of the radially flowing water will be blocked by the stop member 83, thereby forming a dead angle of xcex8 degrees. As such, 360-degree sprinkling cannot be achieved.
The primary object of the invention is to provide an adjustable sprinkler nozzle that is adjustable up to 360 degrees and that does not have any dead angle.
Another object of the invention is to provide an adjustable sprinkler nozzle that utilizes a stepped flange provided at a lower end of a first spiraling face of a cap to abut against an inner wall of a third spiraling face of an upper body to control speed and flow of water, and to ensure complete closing of the nozzle during closing so as to prevent water leakage.